package main

import "fmt"

func containsDuplicate(nums []int) bool {
	m := make(map[int]int)
	for _, value := range nums {
		if _, ok := m[value]; ok {
			return true
		} else {
			m[value] = value
		}
	}
	return false
}

func main() {
	s := []int{1, 2, 3, 5, 5}
	fmt.Println(containsDuplicate(s))
}
